JPS6241826B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold making apparatus that rapidly dries and hardens a mold molded using foundry sand to which a water-soluble binder has been added.

Conventionally, after filling a model box with foundry sand to which a water-soluble binder such as water-soluble glue has been added (hereinafter referred to as foundry sand containing water-soluble glue), the model box is placed in a heating furnace or the like to heat the inside of the model box. It was attempted to dry and harden the foundry sand by evaporating the moisture in the foundry sand, but this method was not widely used due to the long drying time and other reasons. However, in recent years, due to problems such as the disposal of foundry sand, the rising price of synthetic resin binders, and the generation of foul-smelling and harmful gases in shell molding, cold boxing, etc. Molding methods have been reconsidered, and research and improvements have been made to them.

And recently, 80-90 in advance in an airtight container.
After filling a model box with molding sand containing water-soluble glue in a hopper heated to ℃, the pressure inside the model box is reduced to evaporate the moisture in the molding sand in the model box, and the molding sand is dried and hardened. After filling a model box with molding sand containing water-soluble glue at room temperature, heated compressed air is supplied into the model box and passed through the molding sand in the model box to remove moisture from the molding sand. A molding method has also been proposed in which the foundry sand is dried and hardened by evaporation, but while the hardening time is fast in the former method, the temperature of the foundry sand remaining in the hopper may drop or moisture may evaporate. Since blowing performance deteriorates, the molding sand must be measured and heated for each molding, which is seen as a problem from the viewpoint of workability. This has been problematic because it takes a long time to cure, or there are areas where heated compressed air cannot pass through, resulting in uncured areas.

The present invention eliminates the drawbacks of these conventional methods and provides an apparatus for rapidly and efficiently drying and curing molds formed using foundry sand to which a water-soluble binder has been added.

Hereinafter, the achievements of the present invention will be explained based on examples.

Reference numeral 1 designates a column having a head portion 1a protruding from its upper end, and an elevating cylinder 2 is fixed to the front surface of the lower portion thereof, and an elevating table 3 is fixed to the upper end of the piston rod 2a. A slit tube (not shown) is inserted into the lower surface of the head portion 1a above the lifting table 3 with a slight gap between it and the inner periphery, and a blow hole (not shown) passing through the top and bottom is inserted. A blow head 5 having a plurality of blow plates 4 fixed to the lower surface thereof is installed vertically, and the upper end of the blow head 5 penetrates through the head portion 1a, projects above the head portion 1a, and communicates with the sand hopper 6. It's becoming like that. The sand hopper 6 is attached to the upper surface of the head portion 1a via an elastic member 7 to prevent the vibrations of the vibrator 8 from being transmitted to the column 1. A slide gate 9 is slidably provided between the blow head 5 and the sand hopper 6, and the rear end of the slide gate 9 is connected to a piston rod 10a of a gate cylinder 10 attached to the upper surface of the head portion 1a. , due to the operation of the gate cylinder 10,
The communication path between the blow head 5 and the sand hopper 7 can be opened and closed. Reference numeral 11 denotes an upper mold made of a heat-resistant resin material, which has a concave model part on the lower surface and a blow hole (not shown) communicating with the model part on the upper surface. It is attached to the lower surface of the blow head 5 with the blow holes aligned. Drying stations are arranged symmetrically on both sides of the blowing station constructed in this way, and the drying stations have the following construction. That is, 1
Reference numeral 2 denotes a gate-shaped frame consisting of a vertical frame 12a erected from the foundation and a horizontal frame 12b connecting the upper end of the vertical frame 12a. , a guide rail 13 is formed. 1
4 has an opening on the lower surface that can surround the lower mold 15,
The cover member 14 is provided with a heated compressed air supply hole 14a that communicates with the inner hollow portion on the wall surface, and a pair of bearings 16 are mounted on the upper surface of the cover member 14 with a predetermined interval left and right. A rotary shaft 17 is rotatably supported on the bearing 16, and the guide rail 1 is mounted on both ends of the rotary shaft 17.
A wheel 18, which can be engaged with 3, is fixed. Also,
A portal frame 12 is provided at the rear end of the cover member 14.
A piston rod 21a of a travel cylinder 21 rotatably supported is connected via a support bracket 20 to the upper surface of a support frame 19 projecting rearward from the support frame 19. When the travel cylinder 21 operates, the cover member 14 moves the wheel 18. It is adapted to be moved in the front and back direction while being engaged with the guide rail 13. Below the cover member 14, a lifting cylinder 22 is attached upward to the center of a pedestal 23, and a lifting table 24 is fixed to the upper end of the piston rod 22a, and can be raised and lowered by the operation of the lifting cylinder 22. It is provided. Reference numeral 25 rotatably supports flanged rollers 26 at approximately equal intervals left and right, and a lifting table 3 is supported in the front and back direction.
The conveyance path 25 is constructed between the blowing station and the drying station, and cylinder brackets are mounted on support stands 27 on both outer sides of the conveyance end. Bogie cylinders 29, which are rotatably supported via cylinders 28, are provided with their tips facing inward, and the piston rods 29a have a
Frame-shaped transport carts 30 with openings penetrating upward and downward are connected to each other, and by the operation of the cart cylinder 29, they can travel on the transport path 25 between the blowing station and the drying station. It is provided. Further, as shown in FIG.
A surface plate 34 having a through hole 32 communicating with the hollow chamber 31 on the upper surface and an exhaust hole 33 communicating with the outside from the hollow chamber 31 on the side surface is mounted so as to be movable upwardly and downwardly. In addition, the surface plate 3
4 is made of a heat-resistant resin material and has a recess 37 on the lower surface through a sealing member 36 bored through the communication hole 35, and a plurality of ventilation holes 38 on the upper surface communicating with the recess 37. The lower mold 15 is placed so as to be movable up and down with the recess 37 located in the through hole 32 and the communication hole 35.

Reference numeral 39 denotes a hot air generator consisting of three cylindrical bodies 39a each containing a built-in heating device capable of raising the temperature of compressed air to a predetermined temperature. A discharge hole 41 of the cylindrical body 39a at the other end is connected to the source.
is connected to the supply hole 14a of the cover member 14 through a heat-resistant flexible tube and an on-off valve (not shown), and the compressed air supplied from the supply hole 40 gradually passes through each cylindrical body 39a. The temperature is raised and the fuel is supplied into the cover member 14 through a discharge hole 41, a conduit, and an on-off valve (not shown).

42 is a mold left on the upper surface of the lower mold 15.
Note that 43 and 44 are guide pins for preventing the lifting table 3 and the lifting table 24 from rotating in a horizontal plane, respectively.

Next, the operation of such a device will be explained.

Transport cart 30 on which surface plate 34 and lower die 15 are placed
enters directly above the elevating table 3 and operates the elevating cylinder 2 to raise the elevating table 3 and remove the surface plate 34 and lower mold 15 directly above the elevating table 3.
is lifted to fit the lower die 15 to the upper die 11, and then the gate cylinder 10 is operated to open the slide gate 9 and the molding sand in the sand hopper 6 is thrown into the blow head 5. Next, the gate cylinder 10 is operated in reverse to close the slide gate 9 and compressed air is supplied into the blow head 5 to blow the molding sand in the blow plate 4 and the blow hole (not shown) of the upper mold 11. Upper mold 1 through
The cavity consisting of the mold 1 and the lower mold 23 is filled by blowing. Next, reversely operate the lifting cylinder 2,
The lifting table 3 is lowered, the lower mold 15 is released from the upper mold 11, and the lower mold 15 holding the surface plate 34 and the mold 42 is left on the upper surface of the transport vehicle 30, and then the lifting table 3 is returned to its original position. Lower it (see Figure 1). On the other hand, during this time, the right side (first
In the drying station (in the figure), a drying operation is performed on the mold 42 that is placed on the upper surface of the transport vehicle 30 and transported directly above the lifting table 24.
That is, when the surface plate 34 and the lower mold 15 holding the mold 42 placed on the upper surface of the transport vehicle 30 are transported directly above the lifting table 24, the travel cylinder 21 is activated and the cover member 14 is moved vertically to the lifting table 24. The lifting table 24 is advanced to the upper position, and then raised by the operation of the lifting cylinder 22, and the lower mold 15 holding the surface plate 34 and the mold 42 is raised.
is raised until the upper surface of the surface plate 34 comes into contact with the lower end surface of the cover member 14 via the seal member 36,
The mold 42 and the lower mold 15 are hermetically covered by the cover member 14 (see FIG. 1). Next, when an on-off valve (not shown) is opened and heated compressed air is supplied from the hot air generator 39 into the cover member 14 for a predetermined period of time, the mold 42 on the upper surface of the lower mold 15 evaporates moisture and is dried and hardened.

Then, the heated compressed air passes through the mold 42, passes through the ventilation hole 38, the recess 37, the communication hole 35, the through hole 32, and the hollow chamber 31, and is discharged to the outside from the exhaust hole 33. After drying and hardening of the mold 42, the lifting cylinder 2
2 is operated in reverse, the lifting table 24 is lowered to leave the surface plate 34 and the lower mold 15 holding the mold 42 on the upper surface of the transport carriage 30, and the lifting table 24 is subsequently lowered to the original position. after that,
By reversely operating the travel cylinder 21, the cover member 14
is moved back and the mold 42 on the upper surface of the lower mold 15 is taken out.

At this time, since the upper half of the mold 42 is in direct contact with the heated compressed air, water is easily evaporated and the mold 42 is dried and hardened quickly.

On the other hand, the blow-filled mold 42 at the blowing station position is moved to the left drying station position by the reverse operation of the truck cylinder 29 together with the surface plate 34 and the lower die 15 placed on the upper surface of the conveyor truck 30. Then the drying operation is performed. Then, the conveyor cart 30 on which the surface plate 34 and the lower mold 15 are placed at the drying station position on the right side
is moved to the blowing station position by the operation of the truck cylinder 29, and a blowing operation is performed.

In this way, at the blow station position,
While the blowing operation is being performed, the drying operation is repeated at the other drying station position.

In addition, in the above embodiment, the lifting table 2
The lower die 15 is placed on the top surface of the mold 4 via a box-shaped surface plate 34, but the surface plate 34 is placed directly on the top surface of the lifting table 24, which has a communication hole extending from the top surface to the side to the outside. Alternatively, if the lower mold 15 is larger than the lifting table 24, it may be placed between the lifting table 24 and the lower mold 15 via a plate provided with a communication hole.

Further, in the above embodiment, the upper die 11 was fixed to the lower surface of the blow head 5, but the upper die 11 may be left on the upper surface of the support member so as to be movable up and down, or the upper die 11 may be moved up and down with a cylinder. It may also be configured to move.

In short, the present invention has a lifting table that can be raised and lowered and an opening that can surround the lower mold on the lower surface, and
A drying station consisting of a cover member having a supply hole communicating with an internal hollow chamber on a wall surface is disposed on both sides of the blowing station, and a conveyor cart is provided alternately and movably between the blowing station and the drying station. Since the configuration was
It has various excellent effects such as short drying time, even molds with complex shapes can be dried evenly, and two drying stations are installed, which speeds up molding speed and improves productivity. , the effect of contributing to this type of industry is extremely significant.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing an embodiment of the present invention, Fig. 2 is a plan view of Fig. 1, Fig. 3 is a side view of Fig. 1, and Fig. 4 shows a lower mold holding a mold. FIG. 3 is an enlarged sectional view showing a state covered with a cover member. 3: Elevating table, 5: Blow head, 14:
Cover member, 14a: Supply hole, 24: Lifting table, 25: Conveyance path, 30: Conveyance truck.

Claims (1)

[Claims] 1. A blowing station with a blow head fixed above an elevating table, a lifting table arranged on both sides of the blowing station that can be raised and lowered, and an opening fixed above the pair of lifting tables and capable of enclosing a lower mold on the lower surface. and a cover member having a supply hole communicating with the inner hollow chamber in the wall surface, and a cover member having a wall surface and having a supply hole communicating with the internal hollow chamber; A mold making device comprising: a conveyor truck;